Peripheral Arterial Disease (PAD)

The narrowing or hardening of arteries by fatty deposits – also known as Atherosclerosis – can happen in other parts of the body, and not just in the arteries of the heart.

The type of arteries that are frequently affected by Atherosclerosis are:

• Heart (Coronary arteries)
• Lower Limbs (Peripheral arteries)
• Neck (Carotid arteries)

Peripheral Artery Disease (PAD) is a common condition where the blood vessels in your arms or legs become narrowed due to the buildup of fatty deposit, reducing blood flow - especially to your legs.

When blood vessels in your feet and legs are narrowed or blocked by the buildup of plaque (or fats), blood flow to these areas are reduced. As a result, minor problems such as cuts, sores, or blisters may not heal quickly, or may not heal at all. 

Poor blood flow (circulation) in the feet and legs can lead to: 

• Higher cardiovascular risks throughout the body (e.g. heart attack and stroke).
• Deterioration in walking capacity.
• Chronic pain in the foot and toes.
• Ulcer or gangrene; and even loss of the limbs, depending on the severity of the disease.
• Delay wound healing.
• Increase risk of infection.
• Require surgery or treatment procedures, such as angioplasty (unblocking of blood vessels through ballooning or stenting), removal of damaged tissue or even limb amputation.

PAD may not cause symptoms at all, or only mild symptoms. Common signs include:

• Leg pain when walking.
• Muscle pain or cramping in the arms or legs, often in the calf.
• Numbness or weakness in the legs.
• Slow-healing sores on the toes, feet, or legs.
• Change in the colour of the legs (pale or bluish).
• Weak or absent pulse in the legs or feet.

You are more likely to be at risk of PAD if you are:

• More than 50 years of age
• A smoker
• Suffering from diabetes, hypertension or hyperlipidaemia
  

Diagnosis of PAD is not difficult. Firstly, your doctor will identify the symptoms and evaluate your medical history. Your lower limbs and pulse will be examined at various positions. 

Secondly, a clinical assessment of your feet and toes will take place. Through this, the ratio between the highest ankle arterial pressure and brachial artery pressure, also known as Ankle-Brachial Index (ABI), will be taken. A normal ratio would be less than 1.0. However, a narrowed lower limb artery will result in a diminished Ankle-Brachial Index. 

Depending on the severity of the disease and other clinical findings, further investigations may be needed.

If you have diabetes, you are at a higher risk of developing PAD. 

High blood sugar can also cause nerve damage – a condition known as neuropathy – which may mask the symptoms of PAD, making early detection more difficult. This could also possibly lead to:

• Numbness or reduced sensation in the feet.
• Changes in foot shape (e.g., collapsed arched, toe deformities).
• Increased risk of calluses and ulcers (wounds) due to additional factors of improper or inadequate footwear.

With nerve damage in your legs due to high blood sugar, you may not feel:

• A pebble inside your sock that is causing a sore.
• A blister caused by poorly fitting shoes.

The good news is that people with PAD and diabetes can prevent serious foot problems and amputations with good blood sugar control and daily foot care, to help protect their feet.

Preventive tips:  

• Keeping your blood sugar well controlled. 
• Getting an annual foot screening by your doctor or nurse.
• Practicing proper daily foot care. 

1. Cleaning your feet

• Wash your feet daily with mild soap and water.
• Thoroughly dry your feet, especially between the toes.
• Regularly apply moisturiser to prevent dryness and cracking.

2. Checking your feet

• Examine your feet daily for cuts, swelling, redness, blisters or pus discharge. Pay attention to the areas between your toes, heels and soles. 
• Use a mirror or ask for assistance if you have difficulty inspecting your soles.

3. Trimming your toenails

• Trim your toenails weekly, cutting straight across without cutting too short. 
• Smooth the edges with a nail file.
• Avoid cutting the corners of your nails.

4. Dealing with corns and calluses

• Do not use acid treatments or corn plasters. 
• Apply 10% urea cream to soften corns. If ineffective, consult a podiatrist or doctor.
• Refrain from using sharp instruments on your feet.

5. Cleaning wounds on your feet

• Clean wounds with normal saline and dry the area carefully. 
• Apply an antiseptic and cover with a clean, dry dressing.
• Monitor the wound daily and consult your doctor or podiatrist if there is no improvement after two days.

6. Choosing the right footwear

• Always wear shoes, even indoors, to protect your feet. 
• Choose comfortable, well-fitting shoes.
• Always wear cotton socks or stockings with shoes, ensuring they are not too tight.
• Avoid open-toed slippers and massage slippers.

7. Things to avoid

• Do not soak your feet in extremely cold or hot water. 
• Avoid applying moisturisers between your toes.
• Refrain from using massage machines, undergoing foot reflexology or acupuncture.

There are three goals for PAD treatments:

• Reducing cardiovascular risk
• Preventing lower limb loss
• Restoring walking capacity and improving quality of life

To control the narrowing of blood vessels due to buildup of fatty deposits, you are encouraged to undergo:

• Regular screening of risk factors, i.e. diabetes and cholesterol screening
• Change of lifestyle - quit smoking, low cholesterol diet, moderate exercise, weight reduction
• Taking anti-platelet agents - long term anti-platelet agents (eg. aspirin, plavix, ticlid) reduce the risk of all cardiovascular disease
• Taking statins (e.g. simvastatin, atorvastatin, rosuvastatin or crestor) - to reduce fat deposits in the arteries.

Non-surgical treatment of PAD includes:

1. Walking exercise - regular walking exercise of at least 50 minutes, three or more times per week, can help most people with intermittent pain or discomfort when undergoing physical activity due to lack of blood flow, also known as claudication.
2. Medication to reduce intermittent claudication symptoms are also available.

These non-surgical treatments are only applicable for certain inpatients with significant symptoms, with the aim to improve the blood supply to the affected tissues. However, if an ulcer or gangrene has already been set in, surgical debridement (removal of dead, damaged, or infected tissue to promote healing) will be needed.

Surgical treatment of PAD includes:

The narrowed arteries can be opened using various equipment including guidewires, angioplasty balloons, atherectomy catheters, and stents under X-ray. The procedure will be carried out through a puncture over the groin region under local or regional anaesthesia.

A bypass can be made between the unobstructed arteries, also known as patent arteries, above and below the site of obstruction. Surgical Incisions are needed to expose the arteries for bypass. Either the patient's own vein or a synthetic bypass graft can be used as the bypass conduit.

This combination of both endovascular and open bypass treatment is used to treat patients with more complicated arterial occlusive disease.

In special situations where only a short segment of artery is affected by atherosclerotic plaque, an incision can be made over the vessel for the removal of plaque to improve blood flow through the artery.

If an ulcer or gangrene of the toe and foot has already been set in, minor amputation or wound debridement may be necessary to ensure rapid recovery, and also to restore the walking ability of the individual. 

The need for this surgery depends on the location and severity of tissue loss as advised by your specialist.

A foot ulcer can become infected, even with good care. It is important that you know how to spot the early signs of infection, including:

• Redness
• Heat / warmth
• Pain
• Swelling
• Increase in fluid
• Bad smell from wound
• Change in fluid colour (yellow or green)

When should I seek help?

Seek medical help immediately if:

• Wound is not healing well, or worsens
• Signs of infection develops
• Fever develops or if you feel unwell

Find out more about foot care from the following video: